1. Field of the Invention
The present invention generally relates to a location-based service, and more particularly, to a method of building a database needed for implementing a location-based service, and a method of providing a service using the same.
2. Description of the Related Art
In order to recognize a location of an electronic device, a satellite-based system, such as a Global Positioning System (GPS), etc., is generally utilized outdoors. However, since a satellite signal is weak in the city or indoors, it is difficult to utilize such a system in these places. In this case, generally, a method, in which a database is built by collecting a Radio Frequency (RF) signal, such as a Wi-Fi signal, a cellular signal, etc., from each area, and a location is recognized by comparing an RF signal measured by the electronic device with the database, is utilized.
Reference location information is required for building the RF signal database. The database is completed by integrally recording location information serving as a reference and RF signal measurement data, at each point where the database is desired to be built.
Outdoors, location information measured by the GPS serves as a reference location. The database is built in a form of a location of a transmitter for each RF signal or intensity formation of various RF signals at each point, by recording the location information together with an RF signal intensity by the GPS at each point while a data collector moves with a vehicle, and by integrally processing the data.
Since the location recognition by the GPS is impossible indoors, the reference location should be input manually. For example, the data collector collects data by displaying its location on an indoor map, and measuring and recording an RF signal, by itself. Necessary data can be automatically collected in an outdoor area where a GPS signal is received while a data collector moves with a vehicle, so that a database can be built within a relatively short time. However, since a reference location should be manually input in an area such as an indoor area where the GPS signal is not received, costs, such as time, manpower, etc., greatly increase for building of the database. Further, since location-based services provided in the indoor area rather than the outdoor area requires relatively accurate location information, data should be collected with respect to denser points within a service area, so that costs increase more. As a new RF signal is added, an existing RF signal is removed, or the location is changed, with a passing of time, the RF signal information requires continuous maintenance, so that costs continuously increase.